FileSpec.h revision 82cfaed47126a17b4fa21e42e05546e7a041b9e3
1//===-- FileSpec.h ----------------------------------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef liblldb_FileSpec_h_
11#define liblldb_FileSpec_h_
12#if defined(__cplusplus)
13
14#include "lldb/lldb-private.h"
15#include "lldb/Core/ConstString.h"
16#include "lldb/Core/STLUtils.h"
17#include "lldb/Host/TimeValue.h"
18
19namespace lldb_private {
20
21//----------------------------------------------------------------------
22/// @class FileSpec FileSpec.h "lldb/Host/FileSpec.h"
23/// @brief A file utility class.
24///
25/// A file specification class that divides paths up into a directory
26/// and basename. These string values of the paths are put into uniqued
27/// string pools for fast comparisons and efficient memory usage.
28///
29/// Another reason the paths are split into the directory and basename
30/// is to allow efficient debugger searching. Often in a debugger the
31/// user types in the basename of the file, for example setting a
32/// breakpoint by file and line, or specifying a module (shared library)
33/// to limit the scope in which to execute a command. The user rarely
34/// types in a full path. When the paths are already split up, it makes
35/// it easy for us to compare only the basenames of a lot of file
36/// specifications without having to split up the file path each time
37/// to get to the basename.
38//----------------------------------------------------------------------
39class FileSpec
40{
41public:
42    typedef enum FileType
43    {
44        eFileTypeInvalid = -1,
45        eFileTypeUnknown = 0,
46        eFileTypeDirectory,
47        eFileTypePipe,
48        eFileTypeRegular,
49        eFileTypeSocket,
50        eFileTypeSymbolicLink,
51        eFileTypeOther
52    } FileType;
53
54    FileSpec();
55
56    //------------------------------------------------------------------
57    /// Constructor with path.
58    ///
59    /// Takes a path to a file which can be just a filename, or a full
60    /// path. If \a path is not NULL or empty, this function will call
61    /// FileSpec::SetFile (const char *path, bool resolve).
62    ///
63    /// @param[in] path
64    ///     The full or partial path to a file.
65    ///
66    /// @param[in] resolve_path
67    ///     If \b true, then we resolve the path with realpath,
68    ///     if \b false we trust the path is in canonical form already.
69    ///
70    /// @see FileSpec::SetFile (const char *path, bool resolve)
71    //------------------------------------------------------------------
72    explicit FileSpec (const char *path, bool resolve_path);
73
74    //------------------------------------------------------------------
75    /// Copy constructor
76    ///
77    /// Makes a copy of the uniqued directory and filename strings from
78    /// \a rhs.
79    ///
80    /// @param[in] rhs
81    ///     A const FileSpec object reference to copy.
82    //------------------------------------------------------------------
83    FileSpec (const FileSpec& rhs);
84
85    //------------------------------------------------------------------
86    /// Copy constructor
87    ///
88    /// Makes a copy of the uniqued directory and filename strings from
89    /// \a rhs if it is not NULL.
90    ///
91    /// @param[in] rhs
92    ///     A const FileSpec object pointer to copy if non-NULL.
93    //------------------------------------------------------------------
94    FileSpec (const FileSpec* rhs);
95
96    //------------------------------------------------------------------
97    /// Destructor.
98    ///
99    /// The destructor is virtual in case this class is subclassed.
100    //------------------------------------------------------------------
101    virtual
102    ~FileSpec ();
103
104    //------------------------------------------------------------------
105    /// Assignment operator.
106    ///
107    /// Makes a copy of the uniqued directory and filename strings from
108    /// \a rhs.
109    ///
110    /// @param[in] rhs
111    ///     A const FileSpec object reference to assign to this object.
112    ///
113    /// @return
114    ///     A const reference to this object.
115    //------------------------------------------------------------------
116    const FileSpec&
117    operator= (const FileSpec& rhs);
118
119    //------------------------------------------------------------------
120    /// Equal to operator
121    ///
122    /// Tests if this object is equal to \a rhs.
123    ///
124    /// @param[in] rhs
125    ///     A const FileSpec object reference to compare this object
126    ///     to.
127    ///
128    /// @return
129    ///     \b true if this object is equal to \a rhs, \b false
130    ///     otherwise.
131    //------------------------------------------------------------------
132    bool
133    operator== (const FileSpec& rhs) const;
134
135    //------------------------------------------------------------------
136    /// Not equal to operator
137    ///
138    /// Tests if this object is not equal to \a rhs.
139    ///
140    /// @param[in] rhs
141    ///     A const FileSpec object reference to compare this object
142    ///     to.
143    ///
144    /// @return
145    ///     \b true if this object is equal to \a rhs, \b false
146    ///     otherwise.
147    //------------------------------------------------------------------
148    bool
149    operator!= (const FileSpec& rhs) const;
150
151    //------------------------------------------------------------------
152    /// Less than to operator
153    ///
154    /// Tests if this object is less than \a rhs.
155    ///
156    /// @param[in] rhs
157    ///     A const FileSpec object reference to compare this object
158    ///     to.
159    ///
160    /// @return
161    ///     \b true if this object is less than \a rhs, \b false
162    ///     otherwise.
163    //------------------------------------------------------------------
164    bool
165    operator< (const FileSpec& rhs) const;
166
167    //------------------------------------------------------------------
168    /// Convert to pointer operator.
169    ///
170    /// This allows code to check a FileSpec object to see if it
171    /// contains anything valid using code such as:
172    ///
173    /// @code
174    /// FileSpec file_spec(...);
175    /// if (file_spec)
176    /// { ...
177    /// @endcode
178    ///
179    /// @return
180    ///     A pointer to this object if either the directory or filename
181    ///     is valid, NULL otherwise.
182    //------------------------------------------------------------------
183    operator
184    void* () const;
185
186    //------------------------------------------------------------------
187    /// Logical NOT operator.
188    ///
189    /// This allows code to check a FileSpec object to see if it is
190    /// invalid using code such as:
191    ///
192    /// @code
193    /// FileSpec file_spec(...);
194    /// if (!file_spec)
195    /// { ...
196    /// @endcode
197    ///
198    /// @return
199    ///     Returns \b true if the object has an empty directory and
200    ///     filename, \b false otherwise.
201    //------------------------------------------------------------------
202    bool
203    operator! () const;
204
205    //------------------------------------------------------------------
206    /// Clears the object state.
207    ///
208    /// Clear this object by releasing both the directory and filename
209    /// string values and reverting them to empty strings.
210    //------------------------------------------------------------------
211    void
212    Clear ();
213
214    //------------------------------------------------------------------
215    /// Compare two FileSpec objects.
216    ///
217    /// If \a full is true, then both the directory and the filename
218    /// must match. If \a full is false, then the directory names for
219    /// \a lhs and \a rhs are only compared if they are both not empty.
220    /// This allows a FileSpec object to only contain a filename
221    /// and it can match FileSpec objects that have matching
222    /// filenames with different paths.
223    ///
224    /// @param[in] lhs
225    ///     A const reference to the Left Hand Side object to compare.
226    ///
227    /// @param[in] rhs
228    ///     A const reference to the Right Hand Side object to compare.
229    ///
230    /// @param[in] full
231    ///     If true, then both the directory and filenames will have to
232    ///     match for a compare to return zero (equal to). If false
233    ///     and either directory from \a lhs or \a rhs is empty, then
234    ///     only the filename will be compared, else a full comparison
235    ///     is done.
236    ///
237    /// @return
238    ///     @li -1 if \a lhs is less than \a rhs
239    ///     @li 0 if \a lhs is equal to \a rhs
240    ///     @li 1 if \a lhs is greater than \a rhs
241    //------------------------------------------------------------------
242    static int
243    Compare (const FileSpec& lhs, const FileSpec& rhs, bool full);
244
245    static bool
246    Equal (const FileSpec& a, const FileSpec& b, bool full);
247
248    //------------------------------------------------------------------
249    /// Dump this object to a Stream.
250    ///
251    /// Dump the object to the supplied stream \a s. If the object
252    /// contains a valid directory name, it will be displayed followed
253    /// by a directory delimiter, and the filename.
254    ///
255    /// @param[in] s
256    ///     The stream to which to dump the object descripton.
257    //------------------------------------------------------------------
258    void
259    Dump (Stream *s) const;
260
261    //------------------------------------------------------------------
262    /// Existence test.
263    ///
264    /// @return
265    ///     \b true if the file exists on disk, \b false otherwise.
266    //------------------------------------------------------------------
267    bool
268    Exists () const;
269
270
271    //------------------------------------------------------------------
272    /// Expanded existence test.
273    ///
274    /// Call into the Host to see if it can help find the file (e.g. by
275    /// searching paths set in the environment, etc.).
276    ///
277    /// If found, sets the value of m_directory to the directory where
278    /// the file was found.
279    ///
280    /// @return
281    ///     \b true if was able to find the file using expanded search
282    ///     methods, \b false otherwise.
283    //------------------------------------------------------------------
284    bool
285    ResolveExecutableLocation ();
286
287    //------------------------------------------------------------------
288    /// Canonicalize this file path (basically running the static
289    /// FileSpec::Resolve method on it). Useful if you asked us not to
290    /// resolve the file path when you set the file.
291    //------------------------------------------------------------------
292    bool
293    ResolvePath ();
294
295    uint64_t
296    GetByteSize() const;
297
298    //------------------------------------------------------------------
299    /// Directory string get accessor.
300    ///
301    /// @return
302    ///     A reference to the directory string object.
303    //------------------------------------------------------------------
304    ConstString &
305    GetDirectory ();
306
307    //------------------------------------------------------------------
308    /// Directory string const get accessor.
309    ///
310    /// @return
311    ///     A const reference to the directory string object.
312    //------------------------------------------------------------------
313    const ConstString &
314    GetDirectory () const;
315
316    //------------------------------------------------------------------
317    /// Filename string get accessor.
318    ///
319    /// @return
320    ///     A reference to the filename string object.
321    //------------------------------------------------------------------
322    ConstString &
323    GetFilename ();
324
325    //------------------------------------------------------------------
326    /// Filename string const get accessor.
327    ///
328    /// @return
329    ///     A const reference to the filename string object.
330    //------------------------------------------------------------------
331    const ConstString &
332    GetFilename () const;
333
334    TimeValue
335    GetModificationTime () const;
336
337    //------------------------------------------------------------------
338    /// Extract the full path to the file.
339    ///
340    /// Extract the directory and path into a fixed buffer. This is
341    /// needed as the directory and path are stored in separate string
342    /// values.
343    ///
344    /// @param[out] path
345    ///     The buffer in which to place the extracted full path.
346    ///
347    /// @param[in] max_path_length
348    ///     The maximum length or \a path.
349    ///
350    /// @return
351    ///     Returns the number of characters that would be needed to
352    ///     properly copy the full path into \a path. If the returned
353    ///     number is less than \a max_path_length, then the path is
354    ///     properly copied and terminated. If the return value is
355    ///     >= \a max_path_length, then the path was truncated (but is
356    ///     still NULL terminated).
357    //------------------------------------------------------------------
358    size_t
359    GetPath (char *path, size_t max_path_length) const;
360
361    FileType
362    GetFileType () const;
363
364    //------------------------------------------------------------------
365    /// Get the memory cost of this object.
366    ///
367    /// Return the size in bytes that this object takes in memory. This
368    /// returns the size in bytes of this object, not any shared string
369    /// values it may refer to.
370    ///
371    /// @return
372    ///     The number of bytes that this object occupies in memory.
373    ///
374    /// @see ConstString::StaticMemorySize ()
375    //------------------------------------------------------------------
376    size_t
377    MemorySize () const;
378
379    //------------------------------------------------------------------
380    /// Memory map part of, or the entire contents of, a file.
381    ///
382    /// Returns a shared pointer to a data buffer that contains all or
383    /// part of the contents of a file. The data is memory mapped and
384    /// will lazily page in data from the file as memory is accessed.
385    /// The data that is mappped will start \a offset bytes into the
386    /// file, and \a length bytes will be mapped. If \a length is
387    /// greater than the number of bytes available in the file starting
388    /// at \a offset, the number of bytes will be appropriately
389    /// truncated. The final number of bytes that get mapped can be
390    /// verified using the DataBuffer::GetByteSize() function on the return
391    /// shared data pointer object contents.
392    ///
393    /// @param[in] offset
394    ///     The offset in bytes from the beginning of the file where
395    ///     memory mapping should begin.
396    ///
397    /// @param[in] length
398    ///     The size in bytes that should be mapped starting \a offset
399    ///     bytes into the file. If \a length is \c SIZE_MAX, map
400    ///     as many bytes as possible.
401    ///
402    /// @return
403    ///     A shared pointer to the memeory mapped data. This shared
404    ///     pointer can contain a NULL DataBuffer pointer, so the contained
405    ///     pointer must be checked prior to using it.
406    //------------------------------------------------------------------
407    lldb::DataBufferSP
408    MemoryMapFileContents (off_t offset = 0, size_t length = SIZE_MAX) const;
409
410    //------------------------------------------------------------------
411    /// Read part of, or the entire contents of, a file into a heap based data buffer.
412    ///
413    /// Returns a shared pointer to a data buffer that contains all or
414    /// part of the contents of a file. The data copies into a heap based
415    /// buffer that lives in the DataBuffer shared pointer object returned.
416    /// The data that is cached will start \a offset bytes into the
417    /// file, and \a length bytes will be mapped. If \a length is
418    /// greater than the number of bytes available in the file starting
419    /// at \a offset, the number of bytes will be appropriately
420    /// truncated. The final number of bytes that get mapped can be
421    /// verified using the DataBuffer::GetByteSize() function.
422    ///
423    /// @param[in] offset
424    ///     The offset in bytes from the beginning of the file where
425    ///     memory mapping should begin.
426    ///
427    /// @param[in] length
428    ///     The size in bytes that should be mapped starting \a offset
429    ///     bytes into the file. If \a length is \c SIZE_MAX, map
430    ///     as many bytes as possible.
431    ///
432    /// @return
433    ///     A shared pointer to the memeory mapped data. This shared
434    ///     pointer can contain a NULL DataBuffer pointer, so the contained
435    ///     pointer must be checked prior to using it.
436    //------------------------------------------------------------------
437    lldb::DataBufferSP
438    ReadFileContents (off_t offset = 0, size_t length = SIZE_MAX) const;
439
440    size_t
441    ReadFileContents (off_t file_offset, void *dst, size_t dst_len) const;
442
443    //------------------------------------------------------------------
444    /// Change the file specificed with a new path.
445    ///
446    /// Update the contents of this object with a new path. The path will
447    /// be split up into a directory and filename and stored as uniqued
448    /// string values for quick comparison and efficient memory usage.
449    ///
450    /// @param[in] path
451    ///     A full, partial, or relative path to a file.
452    ///
453    /// @param[in] resolve_path
454    ///     If \b true, then we will try to resolve links the path using
455    ///     the static FileSpec::Resolve.
456    //------------------------------------------------------------------
457    void
458    SetFile (const char *path, bool resolve_path);
459
460    bool
461    IsResolved () const
462    {
463        return m_is_resolved;
464    }
465
466    //------------------------------------------------------------------
467    /// Set if the file path has been resolved or not.
468    ///
469    /// If you know a file path is already resolved and avoided passing
470    /// a \b true parameter for any functions that take a "bool
471    /// resolve_path" parameter, you can set the value manually using
472    /// this call to make sure we don't try and resolve it later, or try
473    /// and resolve a path that has already been resolved.
474    ///
475    /// @param[in] is_resolved
476    ///     A boolean value that will replace the current value that
477    ///     indicates if the paths in this object have been resolved.
478    //------------------------------------------------------------------
479    void
480    SetIsResolved (bool is_resolved)
481    {
482        m_is_resolved = is_resolved;
483    }
484    //------------------------------------------------------------------
485    /// Read the file into an array of strings, one per line.
486    ///
487    /// Opens and reads the file in this object into an array of strings,
488    /// one string per line of the file. Returns a boolean indicating
489    /// success or failure.
490    ///
491    /// @param[out] lines
492    ///     The string array into which to read the file.
493    ///
494    /// @result
495    ///     Returns the number of lines that were read from the file.
496    //------------------------------------------------------------------
497    size_t
498    ReadFileLines (STLStringArray &lines);
499
500    //------------------------------------------------------------------
501    /// Resolves user name and links in \a src_path, and writes the output
502    /// to \a dst_path.  Note if the path pointed to by \a src_path does not
503    /// exist, the contents of \a src_path will be copied to \a dst_path
504    /// unchanged.
505    ///
506    /// @param[in] src_path
507    ///     Input path to be resolved.
508    ///
509    /// @param[in] dst_path
510    ///     Buffer to store the resolved path.
511    ///
512    /// @param[in] dst_len
513    ///     Size of the buffer pointed to by dst_path.
514    ///
515    /// @result
516    ///     The number of characters required to write the resolved path.  If the
517    ///     resolved path doesn't fit in dst_len, dst_len-1 characters will
518    ///     be written to \a dst_path, but the actual required length will still be returned.
519    //------------------------------------------------------------------
520    static size_t
521    Resolve (const char *src_path, char *dst_path, size_t dst_len);
522
523    //------------------------------------------------------------------
524    /// Resolves the user name at the beginning of \a src_path, and writes the output
525    /// to \a dst_path.  Note, \a src_path can contain other path components after the
526    /// user name, they will be copied over, and if the path doesn't start with "~" it
527    /// will also be copied over to \a dst_path.
528    ///
529    /// @param[in] src_path
530    ///     Input path to be resolved.
531    ///
532    /// @param[in] dst_path
533    ///     Buffer to store the resolved path.
534    ///
535    /// @param[in] dst_len
536    ///     Size of the buffer pointed to by dst_path.
537    ///
538    /// @result
539    ///     The number of characters required to write the resolved path, or 0 if
540    ///     the user name could not be found.  If the
541    ///     resolved path doesn't fit in dst_len, dst_len-1 characters will
542    ///     be written to \a dst_path, but the actual required length will still be returned.
543    //------------------------------------------------------------------
544    static size_t
545    ResolveUsername (const char *src_path, char *dst_path, size_t dst_len);
546
547    enum EnumerateDirectoryResult
548    {
549        eEnumerateDirectoryResultNext,  // Enumerate next entry in the current directory
550        eEnumerateDirectoryResultEnter, // Recurse into the current entry if it is a directory or symlink, or next if not
551        eEnumerateDirectoryResultExit,  // Exit from the current directory at the current level.
552        eEnumerateDirectoryResultQuit   // Stop directory enumerations at any level
553    };
554
555    typedef EnumerateDirectoryResult (*EnumerateDirectoryCallbackType) (void *baton,
556                                                                        FileType file_type,
557                                                                        const FileSpec &spec
558);
559
560    static EnumerateDirectoryResult
561    EnumerateDirectory (const char *dir_path,
562                        bool find_directories,
563                        bool find_files,
564                        bool find_other,
565                        EnumerateDirectoryCallbackType callback,
566                        void *callback_baton);
567
568protected:
569    //------------------------------------------------------------------
570    // Member variables
571    //------------------------------------------------------------------
572    ConstString m_directory;    ///< The uniqued directory path
573    ConstString m_filename;     ///< The uniqued filename path
574    mutable bool m_is_resolved; ///< True if this path has been resolved.
575};
576
577//----------------------------------------------------------------------
578/// Dump a FileSpec object to a stream
579//----------------------------------------------------------------------
580Stream& operator << (Stream& s, const FileSpec& f);
581
582} // namespace lldb_private
583
584#endif  // #if defined(__cplusplus)
585#endif  // liblldb_FileSpec_h_
586